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From the Publisher:
Grandma has recently bought a house on the marsh, Old Joll, an ancient stone building dating back hundreds of years. Steph, Violet, Luke, Ollie and Tom are back, soon to be joined by their wild, unpredictable cousin Lizzie. What is the strange light that crosses the sky every evening just after sunset? It's a mystery but Lizzie guesses the answer straight away and the excitement begins......
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